The study of the forest in rainy environments of the Dominican Republic reveals the presence of four types of vegetation formations, clearly differentiated from each other in terms of their floristic and biogeographical composition, and also significantly different from the rainforests of Cuba. This leads us to propose two new alliances and four plant associations located in northern mountain areas exposed to moisture-laden winds from the Atlantic: All. Rondeletio ochraceae-Clusion roseae (Ass. Cyatheo furfuracei-Prestoetum motanae; Ass. Ormosio krugii-Prestoetum montanae); and All. Rondeletio ochraceae-Didymopanion tremuli (Ass. Hyeronimo montanae-Magnolietum pallescentis; Hyeronimo dominguensis-Magnolietum hamorii). We pay special attention to the description of cloud forest types, since they have a high rate of endemic species, and therefore there are endemic habitats, which need special protective actions. Therefore, we apply the Shannon diversity index to characteristic, companion, non-endemic, and endemic species. As result, the association Ormosio krugii-Prestoetum montanae has a Shannon_T = 2.4 and a value of Shannon_E = 0, whereas the other 3 associations have a better conservation status with Shannon values in all cases > 0: This is due to a worse conservation status of the Eastern Cordillera, in comparison with the Central Cordillera and Sierra de Bhaoruco. Due to human activity, some areas are very poorly conserved, as evidenced by the diversity index and the presence of endemic tree and plant elements. The worst conserved in terms of the relationship between characteristic plants vegetation (cloud forest) in areas with high rainfall are in the Dominican Republic, along with its floristic diversity and state of conservation. This study has made it possible to significantly increase the botanical knowledge of this important habitat.
Keywords: America; Cuba; cluster analysis; floristic diversity; phytosociology; vegetation.